ADSL 1994 1995 1998 1999 2002 DSL Forum

Ιστορικά Στοιχεία - ADSL 1994 – 1995 – 1998 -1999 – 2002 – DSL Forum Αξιολόγηση των DMT και CAP για ADSL ANSI T 1. 413 ITU-T ADSL standards G. 992. 1 (G. full: 8 M/640 k) καιG. 992. 2 (G. lite: 1. 5 M/512 k) ADSL 2 (G. 992. 3) και (G. 992. 41) 2003 – ADSL 2+ (G. 992. 5). 2004 – VDSL (G. 933. 1) 2006 -- VDSL 2 (G. 933. 2)

Τύποι x. DSL και Standards ¡ Κυριότερες τεχνολογίες x. DSL l l l l ADSL – Αsymmetric Digital Subscriber Line (ANSI TI. 413 - ITU G. 992. 1) ADSL lite (ITU - G. 992. 2) ADSL 2 (ITU - G. 992. 3 - G. 992. 4) ADSL 2+ (ITU - G. 992. 5) HDSL – High-bit-rate Digital Subscriber Line (ITU - G. 991. 1) SHDSL – Symmetric High-bit-rate Digital Subscriber Line (G. 991. 2) VDSL – Very-high-data-rate Digital Subscriber Line (ITU G. 993. 1) VDSL 2 – Very-high-data-rate Digital Subscriber Line (ITU G. 993. 2)

Τύποι x. DSL - Χαρακτηριστικά x. DSL ADSL Περιγραφή Asymmetric Digital Ρυθμός Δεδομένων upstream downstream 64– 640 kbps 1. 5 - 8 Mbps 1. 544 Mbps - 5. 5 km 2. 048 Mbps - 4. 8 km 6. 312 Mbps - 3. 6 km 8. 448 Mbps - 2. 7 km 512 Kbps 1 Mbps 5. 5 km Subscriber Line ADSL lite Splitterless Asymmetric DSL Απόσταση ADSL 2 Asymmetric Digital Subscriber Line 2 1 - 3. 5 Mbps 12 Mbps < 6 km ADSL 2+ Asymmetric Digital Subscriber Line 2 + 1 - 3. 5 Mbps 24 Mbps < 6 km HDSL Symmetric High bitrate Digital Subscriber Line (uses 2– 3 wire pairs) 1. 544 Mbps full duplex (T 1) 2. 048 Mbps full duplex (E 1) 1. 544 Mbps - 5. 5 km 2. 048 Mbps - 3. 6 km SDSL Symmetric DSL (uses 1 wire pairs) 1. 544 Mbps full duplex (T 1) 2. 048 Mbps full duplex (E 1) 3 km (UTP) VDSL Very high rate Digital Subscriber Line 1. 5 - 2. 3 Mbps 13 -52 Mbps asymmetric 26 Mbps symmetric 12. 96 Mbps - 1. 4 km 25. 82 Mbps - 0. 9 km 51. 84 Mbps - 0. 3 km

Σύγκριση απόδοσης 0 0. 6 1. 2 1. 8 2. 5 3. 0 3. 6 4. 3 4. 9 5. 5 6. 0 Distance/km Reference: DSL Forum: DSL Anywhere - Issue 2, Sep. ‘ 04

ΡΥΘΜΟΙ ΔΕΔΟΜΕΝΩΝ Vo. IP Πλοήγηση στον Ιστό Φωτο 5 Mpixel σε 10 s SDTV (Mpeg 4) SDTV (Mpeg 2) HDTV (Mpeg 4) HDTV (Mpeg 2) 8 -64 Kbps 1 Mbp s 1. 5 Mbps 4 Mbps 7 -9 Mbps 15 Mbps

Αρχιτεκτονική ADSL – DSLAM (3) ¡ e. g. X DSLAMs provides scalable 48 port density options to meet the needs of smaller deployments both in-building and in remote cabinets. The Raptor XP family includes support for FE/GE uplinks and 48 ADSL 2+ ports with or without built-in splitters. The Raptor XP also supports a full suite of Layer 2 and Layer 3 capabilities.

Protocol stacks ADSL

Αρχιτεκτονική ADSL - RFC 1483 ¡ ¡ Μοντέλο λειτουργίας δρομολόγησης (routed) και γεφύρωσης (bridged): “Multiprotocol Encapsulation over ATM Adaptation Layer 5” Βridged encapsulation l l l ¡ An ATU-R acts as a bridge between the Ethernet and the wide -area networking (WAN) side. CPE 802. 3 Ethernet frames are segmented into asynchronous transfer mode (ATM) cells through ATM adaptation layer 5 (AAL 5). The receiving equipment is notified of the type of protocol segmented into to cells because the standard calls appending logical linkcontrol/subnetwork access protocol (LLC/SNAP) information to the 802. 3 frame before its segmented into the ATM cells. Routed bridge encapsulation l The packets are not bridged but instead routed based on IP header information.

Αρχιτεκτονική ADSL – Mοντέλο συγκέντρωσης τερματιζόμενων PPP συνδέσεων πάνω από ATM ¡ ¡ The ATU-R encapsulates IP packets into PPP frames and then segments them into ATM cells via AAL 5. The PPP link is terminated at the BRAS and the originating workstation’s IP packet is routed to its final destination through the service provider of choice. Remote Authentication Dial-in User Service (RADIUS) server is used to authenticate and authorize the user -> per session Authentication, Authorization, and Accounting (AAA). DHCP servers are used to assign the IP address to the user. A single PPP session per VC.

Αρχιτεκτονική ADSL – Mοντέλο συγκέντρωσης τερματιζόμενων PPP συνδέσεων πάνω από Ethernet ¡ ¡ ¡ In the PPPo. E architecture, an ATU-R acts as an Ethernetto-WAN bridge and the PPP session is established between the end user’s PC and the access concentrator. The host encapsulates IP packets into PPP frames encapsulated into a MAC frames and then bridging the frame over ATM/DSL. PPP over Ethernet (PPPo. E) provides the ability to connect a network of hosts over a simple bridging access device to a remote Access Concentrator. Each host utilizes its own PPP stack and the user is presented with a familiar user interface. Access control, billing and type of service can be done on a per-user, rather than a per-site, basis. To provide a point-to-point connection over Ethernet, each PPP session must learn the Ethernet address of the remote peer, as well as establish a unique session identifier. PPPo. E includes a discovery protocol for this.

Local Loop Unbundling Incumbent Network Other Licensed Operator’s (OLOs) Network

Full LLU (Local Loop Unbundling) Κατάργηση ζεύξης

Shared LLU (Local Loop Unbundling)

¡ ¡ ¡ ¡ ¡ DSLAM: Digital Subscriber Line Access Multiplexer BRAS: Broadband Remote Access Server MDF: Main Distribution Frame LE/CO: Local Exchange/Central Office ATU-R: ADSL Transeiver Unit, Remote end ATU-C: ADSL Transeiver Unit, Central Office end AN: Access Node L 2 TP: Layer 2 Tunneling Protocol HPF: High Pass Filter LPF: Low Pass Filter POTS: Plain Old Telephone System AAA: Authentication, Authorization, and Accounting RADIUS: Remote Authentication Dial-in User Service DHCP: Dynamic Host Configuration Protocol LLU: Local Loop Unbundling SM : Services Module PDN: Premises Distribution Network OLO: Other Licensed Operator